SQL-Server Unpivot/Pivot Example - sql

Question

i'm making an application to manage hotel bookings and i need to show the ocupation rate per month in a year. I made a query that kinda solves the problem but i want presented in another format.
My current query return the following table (2x12):
January|February|March|April| ..... and so on
20 15 18 20 ..... and so on
And i want something like this (12x2):
January|20
February|15
March|18
... |...
This is my query:
Select
SUM(CASE WHEN datename(month, [CheckIn]) = 'January' or datename(month, [CheckOut]) = 'January' THEN 1 ELSE 0 END) January,
SUM(CASE WHEN datename(month, [CheckIn]) = 'February' or datename(month, [CheckOut]) = 'February' THEN 1 ELSE 0 END) February,
SUM(CASE WHEN datename(month, [CheckIn]) = 'March' or datename(month, [CheckOut]) = 'March' THEN 1 ELSE 0 END) March,
SUM(CASE WHEN datename(month, [CheckIn]) = 'April' or datename(month, [CheckOut]) = 'April' THEN 1 ELSE 0 END) April,
SUM(CASE WHEN datename(month, [CheckIn]) = 'May' or datename(month, [CheckOut]) = 'May' THEN 1 ELSE 0 END) May,
SUM(CASE WHEN datename(month, [CheckIn]) = 'June' or datename(month, [CheckOut]) = 'June' THEN 1 ELSE 0 END) June,
SUM(CASE WHEN datename(month, [CheckIn]) = 'July' or datename(month, [CheckOut]) = 'July' THEN 1 ELSE 0 END) July,
SUM(CASE WHEN datename(month, [CheckIn]) = 'August' or datename(month, [CheckOut]) = 'August' THEN 1 ELSE 0 END) August,
SUM(CASE WHEN datename(month, [CheckIn]) = 'September' or datename(month, [CheckOut]) = 'September' THEN 1 ELSE 0 END) September,
SUM(CASE WHEN datename(month, [CheckIn]) = 'October' or datename(month, [CheckOut]) = 'October' THEN 1 ELSE 0 END) October,
SUM(CASE WHEN datename(month, [CheckIn]) = 'November' or datename(month, [CheckOut]) = 'November' THEN 1 ELSE 0 END) November,
SUM(CASE WHEN datename(month, [CheckIn]) = 'December' or datename(month, [CheckOut]) = 'December' THEN 1 ELSE 0 END) December
FROM {Booking} INNER JOIN {Status} ON {Booking}.[StatusId] = {Status}.[Id]
WHERE {Booking}.[CheckIn] >= #BeginDate AND {Booking}.[CheckOut] <= #EndDate AND {Status}.[Label] <> 'Canceled'
Any help would be appreciated, i'm stuck and theres is not that much info on the web, thanks!

Answer 1

Looks like you're trying to do an UNPIVOT:
SELECT Month, CheckIns
FROM
(Select
SUM(CASE WHEN datename(month, [CheckIn]) = 'January' or datename(month, [CheckOut]) = 'January' THEN 1 ELSE 0 END) January,
SUM(CASE WHEN datename(month, [CheckIn]) = 'February' or datename(month, [CheckOut]) = 'February' THEN 1 ELSE 0 END) February,
SUM(CASE WHEN datename(month, [CheckIn]) = 'March' or datename(month, [CheckOut]) = 'March' THEN 1 ELSE 0 END) March,
SUM(CASE WHEN datename(month, [CheckIn]) = 'April' or datename(month, [CheckOut]) = 'April' THEN 1 ELSE 0 END) April,
SUM(CASE WHEN datename(month, [CheckIn]) = 'May' or datename(month, [CheckOut]) = 'May' THEN 1 ELSE 0 END) May,
SUM(CASE WHEN datename(month, [CheckIn]) = 'June' or datename(month, [CheckOut]) = 'June' THEN 1 ELSE 0 END) June,
SUM(CASE WHEN datename(month, [CheckIn]) = 'July' or datename(month, [CheckOut]) = 'July' THEN 1 ELSE 0 END) July,
SUM(CASE WHEN datename(month, [CheckIn]) = 'August' or datename(month, [CheckOut]) = 'August' THEN 1 ELSE 0 END) August,
SUM(CASE WHEN datename(month, [CheckIn]) = 'September' or datename(month, [CheckOut]) = 'September' THEN 1 ELSE 0 END) September,
SUM(CASE WHEN datename(month, [CheckIn]) = 'October' or datename(month, [CheckOut]) = 'October' THEN 1 ELSE 0 END) October,
SUM(CASE WHEN datename(month, [CheckIn]) = 'November' or datename(month, [CheckOut]) = 'November' THEN 1 ELSE 0 END) November,
SUM(CASE WHEN datename(month, [CheckIn]) = 'December' or datename(month, [CheckOut]) = 'December' THEN 1 ELSE 0 END) December
FROM {Booking} INNER JOIN {Status} ON {Booking}.[StatusId] = {Status}.[Id]
WHERE {Booking}.[CheckIn] >= #BeginDate AND {Booking}.[CheckOut] <= #EndDate AND {Status}.[Label] <> 'Canceled'
) monthTotals
UNPIVOT
(CheckIns FOR Month IN
(January, February, March, April, May, June, July, August, September, October, November, December)
) AS upvt
Here's a simplified SQLFiddle of this
And here's a doc page on PIVOT and UNPIVOT

Answer 2

You can make your case statements a little shorter/simpler so it's easier to read. MONTH() is a easier to read function and getting rid of else will mean if it simply return a null which SUM() treats like a 0
SELECT [Month], CheckIns
FROM
(
Select
SUM(CASE WHEN MONTH([CheckIn]) = 01 or MONTH([CheckOut]) = 01 THEN 1 END) January,
SUM(CASE WHEN MONTH([CheckIn]) = 02 or MONTH([CheckOut]) = 02 THEN 1 END) February,
SUM(CASE WHEN MONTH([CheckIn]) = 03 or MONTH([CheckOut]) = 03 THEN 1 END) March,
SUM(CASE WHEN MONTH([CheckIn]) = 04 or MONTH([CheckOut]) = 04 THEN 1 END) April,
SUM(CASE WHEN MONTH([CheckIn]) = 05 or MONTH([CheckOut]) = 05 THEN 1 END) May,
SUM(CASE WHEN MONTH([CheckIn]) = 06 or MONTH([CheckOut]) = 06 THEN 1 END) June,
SUM(CASE WHEN MONTH([CheckIn]) = 07 or MONTH([CheckOut]) = 07 THEN 1 END) July,
SUM(CASE WHEN MONTH([CheckIn]) = 08 or MONTH([CheckOut]) = 08 THEN 1 END) August,
SUM(CASE WHEN MONTH([CheckIn]) = 09 or MONTH([CheckOut]) = 09 THEN 1 END) September,
SUM(CASE WHEN MONTH([CheckIn]) = 10 or MONTH([CheckOut]) = 10 THEN 1 END) October,
SUM(CASE WHEN MONTH([CheckIn]) = 11 or MONTH([CheckOut]) = 11 THEN 1 END) November,
SUM(CASE WHEN MONTH([CheckIn]) = 12 or MONTH([CheckOut]) = 12 THEN 1 END) December
FROM [Booking]
INNER JOIN {Status} ON {Booking}.[StatusId] = {Status}.[Id]
WHERE {Booking}.[CheckIn] >= #BeginDate AND {Booking}.[CheckOut] <= #EndDate AND {Status}.[Label] <> 'Canceled'
) MONTHTotals
UNPIVOT
(
CheckIns FOR [Month] IN
(January, February, March, April, May, June, July, August, September, October, November, December)
) AS upvt